Sales figures from the Official Charts Company show it is also just 12,000 copies away from the sixth best-selling album, Dire Straits' long player Brothers In Arms, and is likely to move further up the chart soon.

The company's managing director Martin Talbot said: "As every week goes by, another record seems to tumble in front of Adele.

"Now, her 21 album has overtaken The Dark Side Of The Moon in the all-time biggest sellers list - and by the end of the week, it may well have overtaken Brothers In Arms, too.

"Then she will have Michael Jackson's Thriller in her sights. It has been an extraordinary 12 months or so for Adele, and it looks set to become even more extraordinary as the days and weeks go by." Sales of Adele’s Grammy award-winning album 21 have overtaken those of Michael Jackson’s Bad in the UK.